The present invention relates to a canister for containing a particulate-type product. More particularly, it relates to a canister having venting holes for containing a particulate-type product, such as a ready-to-eat cereal, the venting holes facilitating pressure equilibrium at high altitudes.
An extremely popular form of packaging for dry, particulate-type products sold to consumers is a paper carton. The paper carton normally is rectangular in shape, constructed of one or more layers of paper, and may or may not include an additional plastic liner. A wide variety of products are packaged in this form, ranging from consumable items such as cereals and baking goods, to non-consumable items such as laundry detergents and de-icing salt pellets. Paper cartons present a number of advantages for manufacturers, retailers and consumers. For example, paper cartons are relatively inexpensive to manufacture and provide a number of flat surfaces onto which product or promotional information can be displayed. Due to the rectangular shape, cartons are readily stackable. Thus, a retailer can maximize shelf space while fully displaying the product. Consumers likewise find the stackability characteristic desirable for home storage. Finally, paper cartons are typically sized in accordance with consumer preferences such that a desired amount or volume of product is provided with each individual carton.
Certain types of products are amenable to storage within a paper carton alone. Generally speaking, however, a paper carton cannot, in and of itself, adequately maintain product integrity. For example, a paper carton likely will not prevent aroma, moisture, contaminants, small insects, etc. from passing through to the contained product. Thus, packaging for virtually all particulate-type products requires an additional container or liner disposed within the paper carton. This is especially true for consumable/food products. A widely accepted technique for maintaining product integrity is to place the product into an inner container or bag, that in turn is stored in the carton (commonly referred to as a "bag in a box"). The bag is typically made of a plastic or glassine material and is, in theory, sealed about the product. In this sealed form, the bag maintains product freshness and provides protection against insect infestation, whereas the outer paper carton provides packaging strength and display. Alternatively, a double packaging machine (DPM) technique may be employed to form a plastic or glassine liner within a paper carton. Regardless of the exact manufacturing process, the resulting packaging configuration includes a box with an inner liner that serves as a barrier material. For virtually all applications, a large volume of air will be "contained" within the inner liner in addition to the particulate-type product. That is to say, the particulate-type product will not encompass the entire internal volume of the inner liner, and may include spacing between individual product particles.
As described above, a concerted attempt is made to hermetically seal the inner liner about the particulate-type product. On a mass production basis, however, current packaging technology cannot consistently meet this goal. For example, small openings may remain at an apex of two inner liner film sheets joined to one another. In short, manufacturers accept the fact that some leakage will occur into and out of the inner liner through one or more small openings. Although unexpected, these openings normally are not large enough for passage of contaminants or discharge of product. In fact, the openings may provide a benefit during shipping. Packaged product is typically shipped via truck from the manufacturer to retailers at various locations. The location (e.g., city or town) of a particular retailer often is at a greater altitude than that of the manufacturer, or the route traveled by the truck may include a relatively drastic change in altitude. With increasing altitude, the atmospheric pressure exerted on the carton decreases. Because the carton/inner liner is not hermetically sealed, the pressure differential causes air to vent from the inner liner, thereby bringing an internal pressure of the packaging into equilibrium with the now lower atmospheric pressure. Were the inner liner hermetically sealed, this release of air could not occur, resulting in expansion of the inner liner. This expansion may damage the inner liner/carton. For example, the carton wall(s) may bow, reducing the carton's compression strength (both longitudinal and side-to-side) such that the carton is more susceptible to crushing under typically-encountered forces. Additionally, where a quantity of cartons are closely packed within a corrugated shipping container, expansion of the inner liners may cause the cartons to tightly lodge against one another, rendering removal of the packages from the shipping container extremely difficult.
From a manufacturer's standpoint, box with an inner liner packaging satisfies a number of important criteria including low cost, stackability, and large, flat surfaces for displaying product and promotional information. Unfortunately, however, consumers may encounter several potential drawbacks. These possible disadvantages are perhaps best illustrated by reference to a ready-to-eat cereal product, although it should be understood that a wide variety of other products are similarly packaged.
Most ready-to-eat cereal products are sold to consumers with the box with an inner liner packaging format. To consume the cereal, the user must first open the paper carton. In this regard, a top portion of the carton typically forms at least two flaps folded on top of one another. The flaps are initially at least partially adhered to one another with an adhesive. By pulling or otherwise tearing one flap away from the other, a consumer can then access the inner bag. An all too common problem is that the selected adhesive creates too strong of a bond between the flaps, making flap separation exceedingly difficult.
Once the carton has been opened, the consumer must then open the inner bag. Once again, this may be a cumbersome procedure. More particularly, an elongated seal is typically formed and extends along a top portion of the bag. This seal is broken (or "opened") by pulling apart opposite sides of the bag. In some instances, the so-formed seal is too rigid for simple opening. Even further, a person with reduced dexterity and strength, such as a child or elderly individual, may have difficulty in breaking an even relatively light seal. As a result, attempts at opening the inner bag or liner often result in an undesirable tear along a side of the bag, causing unacceptable product displacement from the bag, or an uneven opening. The consumer may resort to using a knife or scissors, possibly resulting in bodily harm.
Once the carton and bag or liner has been opened, the consumer is then ready to pour the contents from the package. Due to the flexible nature of the inner bag, the actual opening through which the product flows is unpredictable. That is to say, the opening formed in the bag is not uniform or fixed. As a result, a larger than expected volume of product may unexpectedly pour from the container. Alternatively, where the inner bag has not been properly opened, product flow may be unacceptably slow. Further, an inherent bias or bend typically causes the flaps to extend upwardly relative to a top of the carton. Thus, the flaps will impede a user from visually confirming acceptable product volume and flow. Additionally, the inner bag typically is not secured to the carton. During a subsequent pouring operation, then, the entire bag may undesirably release from the carton.
A further consumer concern relating to box with an inner liner packaging stems from attempts to reclose the package for subsequent storage of remaining product. Again with reference to widely employed ready-to-eat cereal packaging, following dispensing of a portion of the cereal from the package, the user is then required to roll or fold the top portion of the bag or liner over onto itself so as to "close" the bag. It is not uncommon for a user to simply forget to perform this operation. Alternatively, even where an attempt is made, the bag cannot be resealed and thus remains at least partially open. Similarly, the bag may subsequently unroll. Individual cereal pieces may be undesirably released from the bag and/or contaminants can enter into the bag. Regardless, a reclosure feature normally associated with the carton normally does not provide an effective barrier to unexpected product displacement and/or contamination due to removal, poor design, misuse, lack of use, etc. These concerns are exacerbated when attempting to store a previously-opened package on its side or when the package is accidentally dropped. In either case, because neither the carton nor the bag provides a complete closure, unanticipated release of cereal from the container may occur.
Viewed as a whole, concerns relating to standard box with an inner liner packaging present numerous opportunities for consumer dissatisfaction. Essentially, consumer preferences for improvements to particulate-type product packaging can be separated into four categories. Consumers prefer that the package be easy to open, easily and satisfactorily reclosed, facilitate consistent and easy pouring and is acceptable for "clean" use by a child or others with limited dexterity. Obviously, consumers further prefer that product costs be as low as possible, and that certain other beneficial attributes associated with the existing box with inner liner packaging continue to be implemented. These existing properties include package strength, product damage protection, use of high volume commercially available materials, visual display of product and promotional material, recycleability, stackability, and moisture, aroma, contaminant and insect protection.
Certain other packaging schemes are available that address, at least in part, several of the above-listed consumer preferences. Unfortunately, however, these packaging techniques entail other drawbacks, thereby limiting their usefulness. For example, rigid plastic containers having removable, sealable lids are available. The greatly increased costs associated with this packaging configuration prohibit its implementation on a mass production basis. Similarly, it may be possible to provide the inner bag with a "zip-lock" sealing feature. While this technique may alleviate several of the reclosure issues previously described, the zip-lock design is expensive and often times does not provide a complete seal. Importantly, with these and other envisioned packaging schemes, consistent formation of a hermetic seal will result in the above-described expansion concerns when the package is shipped to a high altitude location. Once again, because the package technique does not account for necessary venting, an increase in altitude may cause problematic package expansion.
Consumers continue to express a high demand for particulate-type products sold in a paper cartons. However, various problems associated with use of standard packaging, and in particular box with an inner liner packages, may diminish purchasing enthusiasm. Alternative packaging designs may satisfy some consumer concerns, but in fact create new problems, such as deleterious package expansion during shipment to higher altitude locations. Therefore, a need exists for a particulate-type product canister configured to address consumer use preferences while providing adequate venting upon shipment to high elevations.